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71.
Hideya Yamamoto Yasuki Kihara Shinichiro Fujimoto Hiroyuki Daida Kazuhiro Kobuke Yoshitaka Iwanaga Shunichi Miyazaki Tomohiro Kawasaki Takashi Fujii Sachio Kuribayashi 《Journal of Cardiovascular Computed Tomography》2021,15(2):148-153
BackgroundWhether coronary plaque characteristics assessed in coronary computed tomography angiography (CCTA) in association with the coronary artery calcium score (CACS) have predictive value for coronary events is unclear. We aimed to examine the predictive value of the CACS and plaque characteristics for the occurrence of coronary events.MethodsAmong 2802 patients who were analyzed in the PREDICT registry, 2083 with suspected coronary artery disease (CAD) were studied using post hoc analysis. High-risk plaques were defined as having ≥2 adverse characteristics, such as low computed tomographic attenuation, positive remodeling, spotty calcification, and napkin-ring sign. An adjudicative composite of coronary events (cardiac death, nonfatal acute coronary syndrome, and coronary revascularization ≥3 months after indexed CCTA) were analyzed.ResultsSeventy-three (3.5%) patients had coronary events and 313 (15.0%) had high-risk plaques. Multivariate Cox proportional hazard analysis showed that high-risk plaques remained an independent predictor of coronary events (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.13–3.34, P ?= ?0.0154), as well as the log-transformed CACS (adjusted HR 1.24, 95% CI 1.11–1.39, P ?= ?0.0002) and the presence of obstructive stenosis (adjusted HR 5.63, 95% CI 3.22–10.12, P 0.0001). In subgroup analyses, high-risk plaques were independently predictive only in the low CACS class (<100).ConclusionThis study shows that assessment of adverse features by coronary plaque imaging independently predicts coronary events in patients with suspected CAD and a low CACS. Our findings suggest that the clinical value of high-risk plaques to CACS and stenosis assessment appears marginal. 相似文献
72.
Sudden death due to anomalous aortic origin of a coronary artery is far less common among young children in the absence of exercise stress. This report describes the case of a 2-year-old boy with a lower respiratory tract infection who suffered sudden cardiac arrest in his bed at home. The autopsy revealed that the left coronary artery (LCA) originated from the right sinus of Valsalva with an acute angle takeoff and traveled between the aorta and the pulmonary trunk (an interarterial course). Upon histological examination, the LCA, before reaching its major branches, was located adjacent to the outside of the aortic wall without an intramural passage, and the arterial wall was composed almost exclusively of elastic fibers without media containing smooth muscle cells throughout the entire length of the abnormal running. Screening tests for respiratory virus infection detected enterovirus in the lung tissue. In association with an acute angle takeoff and interarterial course, the wall structure with highly abundant elastic fibers that are more flexible tissues among blood vessel components might suggest their vulnerability to compression during the great vessels’ systolic expansion in the sympathetic activation induced by the viral infection, leading to fatal myocardial ischemia without physical exertion. 相似文献
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目的探讨左心室射血分数(LVEF)减低的左冠状动脉异常起源于肺动脉(ALCAPA)的超声心动图特点及手术效果。 方法选取2008年10月至2018年9月首都医科大学附属北京儿童医院ALCAPA患者28例,根据LVEF分为LVEF减低组(LVEF<50%)19例和LVEF正常组(LVEF≥50%)9例,比较2组患者超声心动图表现,应用两独立样本t检验比较2组患者间超声参数的差异。手术患者(17例)分别于术后1 d、1个月、6个月、1年进行超声心动图随访,应用配对t检验与术前超声参数进行对比。 结果LVEF减低组患者LVEF为30%~48%,平均年龄5.4个月;LVEF正常组LVEF为60%~73%,平均年龄2.5岁。LVEF减低组与LVEF正常组相比,左心室舒张末期内径大[(131.95±24.24)mm/m2 vs(85.67±20.26)mm/m2],右冠状动脉内径小[(3.06±0.51)mm vs(4.01±0.62)mm],差异具有统计学意义(t=-4.465、4.075,P均<0.001),易形成室壁瘤。LVEF减低组中10例行手术治疗,7例超声心动图随访至术后1年;与术前相比,术后1 d开始左心室舒张末期内径逐渐回缩[(109.98±16.06)mm/m2、(99.49±12.02)mm/m2、(89.48±10.90)mm/m2、(80.03±8.09)mm/m2 vs(123.26±12.40)mm/m2],差异具有统计学意义(t=-2.668、-7.519、-5.413、-6.526,P=0.004、0.001、0.012、0.007),LVEF术后1个月开始恢复,术后6个月达正常水平[(45.50±9.57)%、(66.25±10.34)%、(67.25±4.50)% vs(38.83±7.05)%],差异具有统计学意义(t=3.162、3.683、5.869,P=0.025、0.014、0.002)。 结论LVEF减低的ALCAPA患儿年龄小、心脏病变重,超声心动图可以准确作出诊断,但需要与心内膜弹力纤维增生症、扩张型心肌病相鉴别。ALCAPA手术治疗远期效果较好,超声心动图在术后随访中有重要作用。 相似文献
75.
目的:运用功能性心肌血流指数(MBFI)评价缺血性冠心病(ICAD)可行性分析。方法:回顾性分析冠心病疑似患者行冠状动脉CT血管成像(CCTA)检查,同期接受有创冠状动脉造影(ICA)及导管法心肌血流储备分数(FFR)检查共81例患者,其中男性43例,女性38例,年龄(59.27±9.09)岁;计算MBFI;以FFR≤0.80为金标准,分别以四格表诊断试验确定MBFI与ICA的最佳切点值来判断ICAD;评价MBFI、ICA的ROC曲线特征及诊断准确度。结果:81例患者,CCTA扫描平均剂量为(3.06±1.22)mSv。MBFI、ICA最佳切点值分别为0.074、70%,25例患者FFR≤0.80。MBFI、ICA两者ROC曲线下面积分别为0.825、0.699(Z=2.024,P=0.0429),其敏感度、特异度、阳性预测值、阴性预测值分别为88.00%、80.35%、66.67%、93.75%和76.00%、51.79%、41.30%、82.86%,诊断准确度分别为82.72%、59.26%(χ2=10.753,P<0.01)。33例患者(40.74%,33/81)ICA狭窄程度为65%或70%,其中27例患者(81.82%,27/33)心肌不缺血,运用MBFI值大于0.074可明确23例患者心肌并不缺血(69.70%,23/33)。结论:MBFI属于功能性指标,可用于排查缺血性冠心病。 相似文献
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79.
Mario Gaudino Filippo Piatti Christopher Lau Francesco Sturla Jonathan W. Weinsaft Luca Weltert Emiliano Votta Nicola Galea Ilaria Chirichilli Antonino Di Franco Marco Francone Carlo Catalano Alberto Redaelli Leonard N. Girardi Ruggero De Paulis 《The Journal of thoracic and cardiovascular surgery》2019,157(2):455-465
Objectives
This study applied advanced 4-dimensional flow magnetic resonance imaging processing to assess differences in aortic flow dynamics after valve sparing root replacement, with and without reconstruction of the Valsalva sinuses.Methods
We enrolled patients after valve sparing root replacement with a straight tubular prosthesis (n = 10) or with a prosthesis with Valsalva neosinuses (n = 10); age-matched subjects without cardiovascular diseases served as controls (n = 10). 4-Dimensional flow magnetic resonance imaging acquisitions were performed on a 3.0T magnetic resonance imaging unit. In-house processing was used to segment the aortic lumen and extract the volumetric 4-dimensional flow velocity field. Velocity flow streamlines were computed to compare the amount of rotational flow and wall shear stress. Occurrence of abnormal wall shear stress (WSS) was estimated within the descending aorta of each surgical group.Results
Physiologic-like sinus vortices were visible in the aortic root when using the prosthesis with neosinuses, whereas straight tubular graft revealed localized intrados malrotations (P = .003 for organized vortical structures vs neosinuses graft and P < .001 vs control). In the ascending aorta, recreation of the sinuses resulted in significantly lower velocity and WSS than in the straight tubular graft (P < .001) and controls (P < .001), these alterations were attenuated in the mid-descending aorta. Incidence of abnormal WSS was markedly higher in the straight tube grafts than neosinus of Valsalva grafts.Conclusions
Re-creation of the sinuses of Valsalva during valve-sparing root replacement is associated with more physiologic flow and significantly lower WSS in the aortic root. Lower WSSs in the distal thoracic aorta is a novel finding with potential implications on distal aortic remodeling. 相似文献80.